1. Field of the Invention
The present invention relates to the field of computer technology, and in particular to a computerized method for predicting the addressee field in an electronic mail system, in which history information associated with the user's sent mail is analyzed for the purpose of associating the most probable addressee for a given e-mail letter.
2. Description of the Related Art
When using electronic mail (e-mail), a user normally must use the addressee's complete electronic address, referred to herein as a TCP-IP address. The user is typically required to use the TCP-IP address in a correct form, because this address is used to route the mail to the intended target mail server. Usually, there is an IP-address of the mail server encoded within the TCP-IP address. The TCP-IP address further includes user-specific ID-information (e.g., the name or nickname of the addressee) so as to distinguish one particular addressee from among a plurality of users registered with the target mail server.
Usually, the TCP-IP-address information itself is not actually entered by the user, but instead, a more readable character string is used. For example, the character string that comprises the TCP-IP address can be converted by the personal e-mail client program into the complete name of a respective person, e.g., “David Miller” might be used and displayed to the user instead of the TCP-IP address “Miller-David@companyX.de”.
This additional information concerning location, organization and/or country is usually added to the user name to make it unique. Sometimes, even a number may be added to the name to generate a unique mail system address.
State of the art e-mail client programs installed at the user's PC do not propose or predict an addressee term, i.e. the addressee's e-mail address, when a new mail is created. Once, however, the user begins to enter some characters into the addressee field in the ‘new message’ window of his e-mail client, some programs will attempt to complete the name based on this initial entry of characters. This is true, for example, for newer versions of Microsoft™ Outlook Express™. A similar procedure is used in Microsoft™ Internet Explorer, Version 6 and many other programs, which append the rest of a stored character string to the initial string entered by a user. A disadvantage of this automatic string-completion is that it requires an initial user action to identify a significant subset of addressees, which are selected from a personal address book stored locally at the user PC, and/or stored in a centralized form at the e-mail server in an intranet or LAN of an enterprise.
If the user creating a new e-mail does not enter anything into the addressee field, prior art techniques disadvantageously do not make any proposal with regard to whom the mail could be addressed, even if the header/subject line is already filled-in by the user, and/or the text of the mail already comprises a considerable number of pages.
If some initial entry, e.g., at least one character, is present in the addressee field, a prior art e-mail program, for example the e-mail client in Lotus Notes™, Release 5, performs the above-mentioned address prediction based on stored addresses at the mail server of an Intranet, but to do that, the user's PC must be connected to the LAN, or to the Intranet, respectively. If the user's PC is cut off from such network, only the locally stored address book may be used for addressee term proposals.
Thus, where access to the complete list of electronic mail addressees is available, i.e., in a “closed world” scenario, where basically all mail addresses are known and can be listed or accessed, a prior art e-mail client may do one of the following solutions when confronted with an incomplete or ambiguous mail address entry:                1. it may reject such incomplete or ambiguous mail address;        2. it may replace an incomplete, but unique name in the mail address field on demand or automatically by the complete, unique mail address, or        3. it may map an incomplete and ambiguous mail address to a complete unique mail address and make a respective proposal, in the event that more than one complete, unique mail address matches. In prior art systems, usually some heuristic methods are used to rank the list of candidates and then the top-candidate is used as the best replacement for the incomplete and ambiguous mail address. These heuristic methods comprise, for example, a comparison of dates of stored e-mail correspondence, or the number of e-mails sent to each respective candidate, whereby the candidate who has the most contacts is proposed as the most likely recipient. Thus, some meta data stored in the history of the user is evaluated in prior art method in order to give the best possible addressee prediction.        
Such predictive methods, however, result in unsatisfactory proposals which, in many cases, are nonsensical and may result in misrouted electronic mail.